What is it?

DIP version with USB connector of the ATtiny84a. The board can be placed in the middle of the breadboard. Sketches can be uploaded from Arduino using the Micronucleus bootloader. There is an indicator LED to determine if the board is in bootloader mode. The push button is connected to the interrupt pin (INT0) and can be used to wake up the board when used in low power applications where sleep mode is required.

Why did you make it?

Using the regular DIP version of the ATtiny84a requires some components to make it work with the Micronucleus bootloader and it takes space on the breadboard. Having this integrated in a single board no only saves space, but it also allows cleaner integration into a final product and it is super light (0.8 gram). Here are some examples:

Mr Echolocation

Capacitor Spider

I use the ATtiny84a often for low power projects and for that reason I added the push button on the interrupt pin. This is not a reset button.

What makes it special?

The small size makes it perfect on a breadboard or to implement into a final project. While there are other similar boards out there for other ATtiny micro-controllers (like the Digispark (ATtiny85), Digispark Pro (ATtiny167) and Wattuino Nanite 841 (ATtiny841), none are designed around the ATtiny84a.

How to use?

Special thanks to Spence Konde for making the Micronucleus bootloader a standard option in his ATtiny core. Follow these instructions to add this core to the Arduino IDE: https://github.com/SpenceKonde/ATTinyCore/blob/master/Installation.md

After a successful install you will find the new boards under Tools -> Boards, and select ATtiny84a (Micronucleus / California STEAM).

You might have to install the Micronucleus drivers manually. See for more information the Quick Gotcha list: https://github.com/SpenceKonde/ATTinyCore

Note!

The fuse to disable the reset pin and use it as a regular I/O pin is not set. This allows updating the firmware or erasing the firmware (when additional memory space is required), but as a result pin#11 can not be used as an input nor output. Setting the fuse to enable pin#11 to be used as an I/O pin can be done with an SPI programmer (for example Arduino as SPI) and AVRDUDE.

Specifications

*Note!

The fuse to disable the reset pin and use it as a regular I/O pin is not set. This allows updating the firmware or erasing the firmware (when additional memory space is required), but as a result pin#11 can not be used as an input nor output. Setting the fuse to enable pin#11 to be used as an I/O pin can be done with an SPI programmer (for example Arduino as SPI) and AVRDUDE.